1. Field of the Invention
The present invention relates to a toilet bar suitable for topical application for cleansing the human body, such as the skin and hair. In particular, it relates to a toilet bar composition that is mild to the skin and which also exfoliates the skin.
2. The Related Art
Exfoliating toilet bars are well known. However, the majority of them are very irritating to the skin due to the fact that they are soap based, have high levels of harsh or marginally effective exfoliants, low levels of moisturizers, or some combination of the preceding. Certain prior art toilet bars with high levels of mild synthetic surfactants (xe2x80x9cSyndetxe2x80x9d) and high levels of moisturizers have been described as optionally having exfoliant particles or beads such as sic polyoxyethylene (polyethylene) beads, walnut shells, and apricot seeds, and the like. See e.g. U.S. Pat. No. 6,376,441; U.S. Pat. No. 6,342,470; U.S. Pat. No. 6,384,000; and U.S. Pat. No. 6,074,998. Surprisingly it has been found that mild toilet bars having one or more syndet surfactants, one or more moisturizers, and exfoliants of a specific particle size range provide the user with enhanced moisturization and exfoliation simultaneously. This causes the user""s exfoliated skin to appear fresh and healthy as it removes the dull layer of dead skin, accompanied with deep cleansing leading to less clogged pores while at the same time moisturizing the skin to minimize irritation and dryness as shown by various art recongnized techniques described below.
While not wishing to be bound by the following skin treatment theories, Applicants believe that exfoliation improves skin cleansing by helping to mechanically remove dirt and oil from the skin. Exfoliation also is believed to aid the process of desquamation. Desquamation is a natural process by which corneocytes are removed from the stratum corneum, which is the top layer of skin cells. Corneocytes are simply the cells that comprise the stratum corneum, and they are constantly being removed as the skin regenerates. Exfoliation aids in removing the flaky corneocytes that are ready to detach from the stratum corneum, and so promotes smoother, less flaky skin.
Other potential health benefits to exfoliation in addition to improved scale (flake) removal and oil removal, as suggested above, are reduction in bacteria on the skin, and increased blood flow to the skin due to the mechanical stimulation.
The inventive bar under actual use conditions is expected to show improvements in skin softness, skin smoothness, and similar consumer perceived benefits such as exfoliation efficiency, mildness, moisturization efficiency, deposition efficiency, cleansing efficiency, and a bar property such as skin abrasiveness, etc. based on changes from the baseline for these measurements using toilet bars without the inventive composition as quantified using the test methods described below.
In one aspect the present invention is a toilet bar, having:
a) a cleansing base including about 20 to 60% by wt. of one or more Syndet surfactants;
b) about 10 to 50% by wt. of a moisturizer; and
c) exfoliant particles wherein at least 25% by wt. of the particles have a particle size dimension along the major axis of the particle of from about 100 microns to about 600 microns.
In another aspect of the invention is a toilet bar made by a process including the steps of:
(a) providing at least one synthetic surfactant, at least one moisturizer, and at least one exfoliant;
(b) mixing the ingredients of step (a) to form a product preblend, at or above a temperature sufficient to render the preblend flowable, until the preblend is substantially uniform, wherein the exfoliant, and a substantial portion of the at least one or more moisturizers is excluded from the preblend;
(c) cooling the resulting product preblend;
(d) optionally milling or refining the cooled product preblend to form pellets;
(e) blending the exfoliant with the substantial portion of one or more of the moisturizers not added to the product preblend formed in step (b) or (c) to form an exfoliant preblend;
(f) mixing the exfoliant preblend with the cooled product preblend in a solids blending device;
(g) refining the product of step (f) at least once; and
(h) extruding and stamping the product into toilet bars.
In another aspect of the invention is a method for simultaneously exfoliating and moisturizing the skin comprising the steps of:
a) providing a bar including
i) a cleansing base including about 20 to 60% by wt. of one or more Syndet surfactants;
ii) about 10 to 50% of a moisturizer; and
iii) exfoliant particles wherein at least 25% by wt. of the particles have a particle size dimension along the major axis of the particle of from about 100 microns to about 600 microns;
b) adding sufficient water to wet the bar and the skin;
c) applying the bar to the skin;
d) rubbing the bar onto the skin for a time sufficient to remove dead skin cells and coat the underlying skin with at least one moisturizer.
In a further aspect of the invention is a method for providing the user with a variable level of exfoliation and moisturization on different regions of the body, including the steps of:
(a) providing a toilet bar, wherein the bar includes
1. a cleansing base including about 20 to 60% by wt. of one or more Syndet surfactants;
2. about 10 to 50% of a moisturizer; and
3. exfoliant particles wherein at least 25% by wt. of the particles have a particle size dimension along the major axis of the particle of from about 100 microns to about 600 microns;
(b) moistening the bar; the body or both;
(c) rubbing the bar on user selected areas of the skin for a time sufficient to remove dead skin cells where substantial exfoliation is desired;
(d) adding sufficient water to the bar to form a lather;
(e) rubbing the lather onto user selected areas of the skin where moisturization without substantial exfoliation is desired for a time sufficient to coat the underlying skin with at least one moisturizer; and,
(f) wherein steps (c) to (e) may be carried out in any sequence by the user.
In one aspect of the present invention is a toilet bar, having:
(a) a cleansing base, preferably having a zein value of less than 50, 40, 30, or 25; the cleansing base including about 20 to 60%; preferably 25 to 55% by wt. of one or more Syndet surfactants;
(b) about 10 to 50%; preferably 20 to 45% by wt. of a moisturizer; and
(c) exfoliant particles wherein at least 25% by wt., preferably at least 50%; of the particles have a particle size dimension along the major axis of the particle of from about 100 microns to about 600 microns; preferably about 100 to 300 microns, and more preferably where the smallest particle in the above weight fraction is 150 microns.
Advantageously, the exfoliant particles have a hardness of less than about 4 Mohs, preferably less than about 3 Mohs. Preferably the exfoliant particles have a color distinct from the cleansing base. Advantageously the inventive bar has a sensory exfoliation index less than or equal to 10, preferably less than or equal to 5, more preferably less than or equal to 3; using the test method defined below. Exfoliant particles are preferably present in the inventive bar at a concentration level of less than about 1%, preferably less than 0.5% by wt. Exfoliant particles greater than 400 microns, preferably 300 microns, are advantageously at a concentration level of less than about 0.25%, preferably less than about 0.05%; and more preferably less than about 0.025% by wt.
Exfoliant particles may advantageously be selected from polyethylene, microcrystalline wax, jojoba esters, amorphous silica, talc, tricalcium orthophosphate, or blends thereof, and the like; preferably polyethylene, microcrystalline wax, jojoba esters.
The inventive bar also contains moisturizers preferably selected from fatty acids, triglycerides, mineral oil, petrolatum, glycerin, polyethylene glycol, or blends thereof and the like; more preferably selected from fatty acids, triglycerides, and most preferably stearic acid, sunflower seed oil. Advantageously the moisturizer to exfoliant ratio is in the range of about 20:1 to 500:1; preferably about 100:1 to 500.
With respect to pH, the inventive bar advantageously provides an aqueous slurry pH of about 4 to 8, preferably about 6 to 8 and preferably includes less than about 10%, preferably less than about 3%, by wt. of soluble soap as defined below.
In another aspect of the invention is a toilet bar made by a process including the steps of:
(a) providing at least one synthetic surfactant, at least one moisturizer, and at least one exfoliant;
(b) mixing the ingredients of step (a) to form a product preblend, at or above a temperature (preferably above 85 C) sufficient to render the preblend flowable, until the preblend is substantially uniform (preferably for about 30 minutes to 1 hour and 30 minutes), wherein the exfoliant, (optionally a fragrance), and a substantial portion of the at least one or more moisturizers is excluded from the preblend (preferably the amount of excluded moisturizer is less than about 5% by weight of the formula, preferably less than about 2% by weight of the formula);
(c) cooling the resulting product preblend (preferably using a chill roll or the like);
(d) optionally milling or refining the cooled product preblend to form pellets;
(e) blending the exfoliant with the substantial portion of one or more of the moisturizers not added to the product preblend formed in step (b) or (c) to form an exfoliant preblend (preferably the remaining moisturizer component is in liquid form or is liquified with heating);
(f) mixing the exfoliant preblend with the cooled product preblend in a solids blending device (preferably a ribbon blade mixer, refiner, and z blade mixer and the like);
(g) refining the product of step (f) at least once; and
(h) extruding and stamping the product into toilet bars.
Preferably the step of blending a fragrance is done either simultaneously with the exfoliant and moisturizer or as a separate step to form the exfoliant preblend.
In another aspect of the invention is a method for simultaneously exfoliating and moisturizing the skin comprising the steps of:
(a) providing a bar including
i) a cleansing base, preferably having a zein value of less than 50, 40, 30, or 25; the cleansing base including about 20 to 60%; preferably 25 to 55% by wt. of one or more Syndet surfactants;
ii) about 10 to 50%; preferably 20 to 45% by wt. of a moisturizer; and
iii) exfoliant particles wherein at least 25% by wt., preferably at least 50%; of the particles have a particle size dimension along the major axis of the particle of from about 100 microns to about 600 microns; preferably about 100 to 300 microns, and more preferably where the smallest particle in the above weight fraction is 150 microns.
iv) Adding sufficient water to wet the bar and the skin;
v) applying the bar to the skin;
vi) rubbing the bar onto the skin for a time sufficient to remove dead skin cells and coat the underlying skin with at least one moisturizer.
In a further aspect of the invention is a method for providing the user with a variable level of exfoliation and moisturization on different regions of the body, including the steps of:
a) providing a toilet bar, wherein the bar includes
i) a cleansing base, preferably having a zein value of less than 50, 40, 30, or 25; the cleansing base including about 20 to 60%; preferably 25 to 55% by wt. of one or more Syndet surfactants;
ii) about 10 to 50%; preferably 20 to 45% by wt. of a moisturizer; and
iii) exfoliant particles wherein at least 25% by wt., preferably at least 50%; of the particles have a particle size dimension along the major axis of the particle of from about 100 microns to about 600 microns; preferably about 100 to 300 microns, and more preferably where the smallest particle in the above weight fraction is 150 microns.
b) moistening the bar; the body or both;
c) rubbing the bar on user selected areas of the skin for a time sufficient to remove dead skin cells where substantial exfoliation is desired;
d) adding sufficient water to the bar to form a lather;
e) rubbing the lather onto user selected areas of the skin where moisturization without substantial exfoliation is desired for a time sufficient to coat the underlying skin with at least one moisturizer; and,
f) wherein steps (c) to (e) may be carried out in any sequence by the user.
The inventive bar under actual use conditions is expected to show improvements in skin softness, skin smoothness, and similar consumer perceived benefits such as exfoliation efficiency, mildness, moisturization efficiency, deposition efficiency, cleansing efficiency, and a bar property such as skin abrasiveness, etc. based on changes from the baseline for these measurements using toilet bars without the inventive composition as quantified using the test methods described below. These skin benefit parameters can also be expressed quantitatively as the ratio of the inventive bar response to the comparative bar response. Where the magnitude of the inventive bar benefit improvement is expected to exceed the numerical result of the comparative bar, the observed ratio will be greater than 1.0; i.e. 1.02, 1.05, 1.07, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.0. Where the magnitude of the inventive bar benefit improvement is expected to fall below the numerical result of the comparative bar, the observed ratio will be less than 1.0; i.e. 0.99, 0.98, 0.97, 0.95, 0.93, 0.90, 0.85, 0.80, 0.70, 0.60, 0.50, 0.40, 0.30, 0.20, or 0.10. Tables 1 to 4 below illustrate how various properties of the inventive bar are expected to compare to four different comparative bars. The test methods that may be used to measure the properties are provided below.
Surfactants:
Surfactants are an essential component of the inventive toilet bar composition. They are compounds that have hydrophobic and hydrophilic portions that act to reduce the surface tension of the aqueous solutions they are dissolved in. Useful surfactants can include anionic, nonionic, amphoteric, and cationic surfactants, and blends thereof.
Anionic Surfactants:
Synthetic Anionic Surfactants
The cleansing composition of the present invention contains one or more non-soap anionic detergents (syndets). Preferably the syndets have a zein value of 50 or less. Zein value may be measured using the test method described below.
The anionic detergent active which may be used may be aliphatic sulfonates, such as a primary alkane (e.g., C8-C22) sulfonate, primary alkane (e.g., C8-C22) disulfonate, C8-C22 alkene sulfonate, C8-C22 hydroxyalkane sulfonate or alkyl glyceryl ether sulfonate (AGS); or aromatic sulfonates such as alkyl benzene sulfonate.
The anionic may also be an alkyl sulfate (e.g., C12-C18 alkyl sulfate) or alkyl ether sulfate (including alkyl glyceryl ether sulfates). Among the alkyl ether sulfates are those having the formula:
RO(CH2CH2O)nSO3M
wherein R is an alkyl or alkenyl having 8 to 18 carbons, preferably 12 to 18 carbons, n has an average value of greater than 1.0, preferably greater than 3; and M is a
solubilizing cation such as sodium, potassium, ammonium or substituted ammonium. Ammonium and sodium lauryl ether sulfates are preferred.
The anionic may also be alkyl sulfosuccinates (including mono- and dialkyl, e.g., C6-C22 sulfosuccinates); alkyl and acyl taurates, alkyl and acyl sarcosinates, sulfoacetates, C8-C22 alkyl phosphates and phosphates, alkyl phosphate esters and alkoxyl alkyl phosphate esters, acyl lactates, C8-C22 monoalkyl succinates and maleates, sulphoacetates, alkyl glucosides and acyl isethionates, and the like.
Sulfosuccinates may be monoalkyl sulfosuccinates having the formula:
R4O2CCH2CH(SO3M)CO2M; and
amide-MEA sulfosuccinates of the formula;
R4CONHCH2CH2O2CCH2CH(SO3M)CO2M
wherein R4 ranges from C8-C22 alkyl and M is a solubilizing cation.
Sarcosinates are generally indicated by the formula:
R1CON(CH3)CH2CO2M,
wherein R1 ranges from C8-C20 alkyl and M is a solubilizing cation.
Taurates are generally identified by formula:
R2CONR3CH2CH2SO3M
wherein R2 ranges from C8-C20 alkyl, R3 ranges from C1-C4 alkyl and M is a solubilizing cation.
The inventive toilet bar composition preferably contains C8-C14 acyl isethionates. These esters are prepared by reaction between alkali metal isethionate with mixed aliphatic fatty acids having from 6 to 12 carbon atoms and an iodine value of less than 20.
The acyl isethionate may be an alkoxylated isethionate such as is described in Ilardi et al., U.S. Pat. No. 5,393,466, titled xe2x80x9cFatty Acid Esters of Polyalkoxylated isethonic acid; issued Feb. 28, 1995; hereby incorporated by reference. This compound has the general formula: 
wherein R is an alkyl group having 8 to 18 carbons, m is an integer from 1 to 4, X and Y are hydrogen or an alkyl group having 1 to 4 carbons and M+ is a monovalent cation such as, for example, sodium, potassium or ammonium.
In another embodiment of the inventive toilet bar, there is less than 5% by wt. of any of the following anionic surfactants: alkyl sulfates, alkyl sulfonates, alkyl benzene sulfonates, alkyl alkoxy sulfates, acyl taurides, acyl sulfates, and polyhydfroxy fatty acid amides either individually or of a blend thereof. Preferably there is less than 1%, and more preferably less than 0.1% by wt. of these surfactants.
Soaps.
The inventive toilet bar may contain soap, preferably it contains less than about 10.0% by wt. of soluble soap, more preferably it contains less than about 5% by wt. of soluble soap. The term xe2x80x9csoapxe2x80x9d is used herein in its popular sense, i.e., the alkali metal or alkanol ammonium salts of alkane- or alkene monocarboxylic acids. Sodium, potassium, mono-, di- and tri-ethanol ammonium cations, or combinations thereof, are suitable for purposes of this invention. In general, sodium, potassium, ammonium, mono-, di-, and tri-ethanol soaps of saturated C8-C14 alkyl chains and unsaturated fatty acids, preferably having C8-C22 alkyl chains, are soluble soaps.
Amphoteric Surfactants
One or more amphoteric surfactants may be used in this invention. Such surfactants include at least one acid group. This may be a carboxylic or a sulphonic acid group. They include quaternary nitrogen and therefore are quaternary amido acids. They should generally include an alkyl or alkenyl group of 7 to 18 carbon atoms. They will usually comply with an overall structural formula: 
where R1 is alkyl or alkenyl of 7 to 18 carbon atoms;
R2 and R3 are each independently alkyl hydroxyalkyl or carboxyalkyl of 1 to 3 carbon atoms;
n is 2 to 4;
m is 0 to 1;
X is alkylene of 1 to 3 carbon atoms optionally substituted with hydroxyl, and
Y is xe2x80x94CO2xe2x80x94 or xe2x80x94SO3xe2x80x94
Suitable amphoteric surfactants within the above general formula include simple betaines of formula: 
and amido betaines of formula: 
where n is 2 or 3.
In both formulae R1, R2 and R3 are as defined previously. R1 may in particular be a mixture of C12 and C14 alkyl groups derived from coconut oil so that at least half, preferably at least three quarters of the groups R1 have 10 to 14 carbon atoms. R2 and R3 are preferably methyl.
A further possibility is that the amphoteric detergent is a sulphobetaine of formula: 
where m is 2 or 3, or variants of these in which xe2x80x94(CH2)3SO3xe2x88x92 is replaced by 
In these formulae R1, R2 and R3 are as discussed previously.
Amphoacetates and diamphoacetates are also intended to be covered in possible zwitterionic and/or amphoteric compounds which may be used such as e.g., sodium lauroamphoacetate, sodium cocoamphoacetate, and blends thereof, and the like.
Nonionic Surfactants
One or more nonionic surfactants may also be used in the toilet bar composition of the present invention.
The nonionics which may be used include in particular the reaction products of compounds having a hydrophobic group and a reactive hydrogen atom, for example aliphatic alcohols, acids, amides or alkylphenols with alkylene oxides, especially ethylene oxide either alone or with propylene oxide. Specific nonionic detergent compounds are alkyl (C6-C22) phenols ethylene oxide condensates, the condensation products of aliphatic (C8-C18) primary or secondary linear or branched alcohols with ethylene oxide, and products made by condensation of ethylene oxide with the reaction products of propylene oxide and ethylenediamine. Other so-called nonionic detergent compounds include long chain tertiary amine oxides, long chain tertiary phosphine oxides and dialkyl sulphoxide, and the like.
The nonionic may also be a sugar amide, such as a polysaccharide amide. Specifically, the surfactant may be one of the lactobionamides described in U.S. Pat. No. 5,389,279 to Au et al. titled xe2x80x9cCompositions Comprising Nonionic Glycolipid Surfactants issued Feb. 14, 1995; which is hereby incorporated by reference or it may be one of the sugar amides described in U.S. Pat. No. 5,009,814 to Kelkenberg, titled xe2x80x9cUse of N-Poly Hydroxyalkyl Fatty Acid Amides as Thickening Agents for Liquid Aqueous Surfactant Systemsxe2x80x9d issued Apr. 23, 1991; hereby incorporated into the subject application by reference.
Cationic Skin Conditioning Agents
An optional component in compositions according to the invention is a cationic skin feel agent or polymer, such as for example cationic celluloses. Cationic cellulose is available from Amerchol Corp. (Edison, N.J., USA) in their Polymer JR (trade mark) and LR (trade mark) series of polymers, as salts of hydroxyethyl cellulose reacted with trimethyl ammonium substituted epoxide, referred to in the industry (CTFA) as Polyquaternium 10. Another type of cationic cellulose includes the polymeric quaternary ammonium salts of hydroxyethyl cellulose reacted with lauryl dimethyl ammonium-substituted epoxide, referred to in the industry (CTFA) as Polyquaternium 24. These materials are available from Amerchol Corp. (Edison, N.J., USA) under the tradename Polymer LM-200, and quaternary ammonium compounds such as alkyldimethylammonium halogenides.
A particularly suitable type of cationic polysaccharide polymer that can be used is a cationic guar gum derivative, such as guar hydroxypropyltrimonium chloride (Commercially available from Rhone-Poulenc in their JAGUAR trademark series). Examples are JAGUAR C13S, which has a low degree of substitution of the cationic groups and high viscosity, JAGUAR C15, having a moderate degree of substitution and a low viscosity, JAGUAR C17 (high degree of substitution, high viscosity), JAGUAR C16, which is a hydroxypropylated cationic guar derivative containing a low level of substituent groups as well as cationic quaternary ammonium groups, and JAGUAR 162 which is a high transparency, medium viscosity guar having a low degree of substitution.
Particularly preferred cationic polymers are JAGUAR C13S, JAGUAR C15, JAGUAR C17 and JAGUAR C16 and JAGUAR C162, especially Jaguar C13S. Other cationic skin feel agents known in the art may be used provided that they are compatible with the inventive formulation.
Other preferred cationic compounds that are useful in the present invention include amido quaternary ammonium compounds such as quaternary ammonium propionate and lactate salts, and quaternary ammonium hydrolyzates of silk or wheat protein, and the like. Many of these compounds can be obtained as the Mackine(trademark) Amido Functional Amines, Mackalene(trademark) Amido functional Tertiary Amine Salts, and Mackpro(copyright) cationic protein hydrolysates from the McIntyre Group Ltd. (University Park, Ill.).
In a preferred embodiment of the invention having a hydrolyzed protein conditioning agent, the average molecular weight of the hydrolyzed protein is preferably about 2500. Preferably 90% of the hydrolyzed protein is between a molecular weight of about 1500 to about 3500. In a preferred embodiment, MACKPRO(trademark) WWP (i.e. wheat germ amido dimethylamine hydrolyzed wheat protein) is added at a concentration of 0.1% (as is) in the bar. This results in a MACKPRO(trademark) WWP xe2x80x9csolidsxe2x80x9d of 0.035% in the final bar formula for this embodiment.
Cationic Surfactants
One or more cationic surfactants may also be used in the inventive self-foaming cleansing composition.
Examples of cationic detergents are the quaternary ammonium compounds such as alkyldimethylammonium halogenides.
Other suitable surfactants which may be used are described in U.S. Pat. No. 3,723,325 to Parran Jr. titled xe2x80x9cDetergent Compositions Containing Particle Deposition Enhancing Agentsxe2x80x9d issued Mar., 27, 1973; and xe2x80x9cSurface Active Agents and Detergentsxe2x80x9d (Vol. I and II) by Schwartz, Perry and Berch, both of which are also incorporated into the subject application by reference.
In addition, the inventive toilet bar composition of the invention may include 0 to 15% by wt. optional ingredients as follows:
perfumes; sequestering agents, such as tetrasodium ethylenediaminetetraacetate (EDTA), EHDP or mixtures in an amount of 0.01 to 1%, preferably 0.01 to 0.05%; and coloring agents, opacifiers and pearlizers such as zinc stearate, magnesium stearate, TiO2, EGMS (ethylene glycol monostearate) or Lytron 621 (Styrene/Acrylate copolymer) and the like; all of which are useful in enhancing the appearance or cosmetic properties of the product.
The compositions may further comprise antimicrobials such as 2-hydroxy-4,2xe2x80x2,4xe2x80x2trichlorodiphenylether (DP300); preservatives such as dimethyloldimethylhydantoin (Glydant XL 1000), parabens, sorbic acid etc., and the like.
The compositions may also comprise coconut acyl mono- or diethanol amides as suds boosters, and strongly ionizing salts such as sodium chloride and sodium sulfate may also be used to advantage.
Antioxidants such as, for example, butylated hydroxytoluene (BHT) and the like may be used advantageously in amounts of about 0.01% or higher if appropriate.
Humectants such as polyhydric alcohols, e.g. glycerine and propylene glycol, and the like; and polyols such as the polyethylene glycols listed below and the like may be used.
Moisturizers, also expressed as either humectants and emollients may be advantageously used in the present invention. The emollient xe2x80x9ccompositionxe2x80x9d may be a single benefit agent component or it may be a mixture of two or more compounds one or all of which may have a beneficial aspect. In addition, the benefit agent itself may act as a carrier for other components one may wish to add to the inventive toilet bar.
Hydrophobic emollients, hydrophilic emollients, or a blend thereof may be used. Preferably, hydrophobic emollients are used in excess of hydrophilic emollients in the inventive toilet bar composition. Hydrophobic emollients are preferably present in a concentration greater than about 10% by weight most preferably greater than about 20% by wt. The term xe2x80x9cemollientxe2x80x9d is defined as a substance which softens or improves the elasticity, appearance, and youthfulness of the skin (stratum corneum) by either increasing its water content, adding, or replacing lipids and other skin nutrients; or both, and keeps it soft by retarding the decrease of its water content.
Useful emollients include the following:
(a) silicone oils and modifications thereof such as linear and cyclic polydimethylsiloxanes; amino, alkyl, alkylaryl, and aryl silicone oils;
(b) fats and oils including natural fats and oils such as jojoba, soybean, sunflower, rice bran, avocado, almond, olive, sesame, persic, castor, coconut, mink oils; cacao fat; beef tallow, lard; hardened oils obtained by hydrogenating the aforementioned oils; and synthetic mono, di and triglycerides such as myristic acid glyceride and 2-ethylhexanoic acid glyceride;
(c) waxes such as carnauba, spermaceti, beeswax, lanolin, and derivatives thereof;
(d) hydrophobic and hydrophillic plant extracts;
(e) hydrocarbons such as liquid paraffins, vaseline, microcrystalline wax, ceresin, squalene, pristan and mineral oil;
(f) higher fatty acids such as lauric, myristic, palmitic, stearic, behenic, oleic, linoleic, linolenic, lanolic, isostearic, arachidonic and poly unsaturated fatty acids (PUFA);
(g) higher alcohols such as lauryl, cetyl, stearyl, oleyl, behenyl, cholesterol and 2-hexydecanol alcohol;
(h) esters such as cetyl octanoate, myristyl lactate, cetyl lactate, isopropyl myristate, myristyl myristate, isopropyl palmitate, isopropyl adipate, butyl stearate, decyl oleate, cholesterol isostearate, glycerol monostearate, glycerol distearate, glycerol tristearate, alkyl lactate, alkyl citrate and alkyl tartrate;
(i) essential oils and extracts thereof such as mentha, jasmine, camphor, white cedar, bitter orange peel, ryu, turpentine, cinnamon, bergamot, citrus unshiu, calamus, pine, lavender, bay, clove, hiba, eucalyptus, lemon, starflower, thyme, peppermint, rose, sage, sesame, ginger, basil, juniper, lemon grass, rosemary, rosewood, avocado, grape, grapeseed, myrrh, cucumber, watercress, calendula, elder flower, geranium, linden blossom, amaranth, seaweed, ginko, ginseng, carrot, guarana, tea tree, jojoba, comfrey, oatmeal, cocoa, neroli, vanilla, green tea, penny royal, aloe vera, menthol, cineole, eugenol, citral, citronelle, borneol, linalool, geraniol, evening primrose, camphor, thymol, spirantol, penene, limonene and terpenoid oils;
(j) lipids such as cholesterol, ceramides, sucrose esters and pseudo-ceramides as described in European Patent Specification No. 556,957;
(k) vitamins, minerals, and skin nutrients such as milk, vitamins A, E, and K; vitamin alkyl esters, including vitamin C alkyl esters; magnesium, calcium, copper, zinc and other metallic components;
(l) sunscreens such as octyl methoxyl cinnamate (Parsol MCX) and butyl methoxy benzoylmethane (Parsol 1789);
(m) phospholipids;
(n) antiaging compounds such as alpha hydroxy acids, beta hydroxy acids; and
(o) mixtures of any of the foregoing components, and the like.
Preferred emollient benefit agents are selected from fatty acids, triglyceride oils, mineral oils, petrolatum, and mixtures thereof. Further preferred emollients are fatty acids.
Exfoliants
The inventive bar contains exfoliant particles that help remove dry skin. Not being bound by theory, the degree of exfoliation depends on the size and morphology of the particles, and their hardness. Large, rough and hard articles are usually very harsh and irritating. Very small particles that are very soft may not serve as effective exfoliants. Hardness is typically measured using the Moh scale. The Moh""s scale of hardness is the method used to measure the ability of one substance to scratch another. The scale ranges in order of increasing relative hardness from 1 (softest) to 10 (hardest).
Common exfoliants used in the art include natural minerals such as silica, talc, calcite, pumice, tricalcium phopshate; seeds such as rice, apricot seeds, etc; crushed shells such as almond and walnut shells; oatmeal; polymers such as polyethylene and polypropylene beads, flower petals and leaves; microcrystalline wax beads; jojoba ester beads, and the like. These exfoliants come in a variety of particle sizes and morphology ranging from micron sized to a few mm. They also have a range of hardness. Some examples are given in table 5 below.
The exfoliants in the present invention have particle sizes where at least 25% by weight of the particles (preferably at least 50%) have a major axis (i.e. the longest dimension of an irregularly shaped particle or the diameter of a spherical particle) in the range of about 100 to 600 microns; preferably about 100 to 300 microns, and most preferably where the smallest particle in this weight fraction has its major axis greater than 150 microns; and wherein the exfoliant particle has a hardness of less than about 4, or preferably less than about 3.
Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material ought to be understood as modified by the word xe2x80x9caboutxe2x80x9d.